The billionaire founder of the private space company SpaceX wants to build a colony for 80,000 people on Mars.

At a talk given at the Royal Aeronautical Society, Elon Musk said that he hoped to one day build the permanent village based on sustainable technology.

And yes, it would be vegetarians only.

"At Mars, you can start a self-sustaining civilisation and grow it into something really big," he told the society, according to Wired and Space.com.

Musk said that he would ideally start with a crew of about 10 people, who would build the infrastructure necessary to support larger amounts of brave pioneers willing to brave its harsh atmosphere and high levels of radiation for science.

And no - it wouldn't be a return trip.

"Some money has to be spent on establishing a base on Mars. It's about getting the basic fundamentals in place. That was true of the English colonies -- it took a significant expense to get things started. But once there are regular Mars flights, you can get the cost down to half a million dollars for someone to move to Mars. Then I think there are enough people who would buy that to have it be a reasonable business case."

Musk hopes that repeated flights would bring the cost down and make travel to Mars affordable for more people - just as it has with SpaceX's current cargo flights to the International Space Station, which are unmanned.

Musk has previously said that he would want to make the cost of a flight to Mars about $500,000 per person.

After further thought, he says the first pioneers would go to Mars with large amounts of equipment including machines to make fertiliser, methane and oxygen. The idea would be to produce those substances from the nitrogen and carbon dioxide already plentiful on the planet.

But don't pack your bags just yet - as Wired notes, there are still a few niggling worries to sort out, including how to get there, how to get there alive and how to keep people sane once they realise they can never go home.